There is increasing evidence that immobilization for long periods of time on any form of transportation especially airline flights puts people at risk for deep vein thrombosis (DVT). DVT, blood clots inside veins found deep in extremities or body cavities, is a common disorder. A venous thrombus is a clump of blood cells, platelets, and fibrin (clot) which attaches to the inside walls of veins, can grow in size, and break off to travel downstream from the clot. If the clot stays localized, it can cause swelling and vein irritation. If part of it breaks off, then it can cause blockage downstream, may travel to the lungs (pulmonary embolus) and result in serious illness or even death. In some circumstances, deep vein thrombosis may also contribute to other serious medical problems such as heart attack and stroke.

While superficial venous thrombosis usually is accompanied by redness and tenderness along the course of the involved vein, deep venous thrombosis may not be accompanied by any symptoms at all. Symptoms of DVT, if present, usually include swelling of the involved extremity with local tenderness deep within the muscles in the area. If the DVT occurs in veins such as those in the pelvis there may be no symptoms. In these cases the first sign of DVT may be one of the complications mentioned above such as pulmonary embolus. Therefore, prevention is key to saving injuries and lives.

Immobilization (bed rest, long trips, etc.); Smoking; Cramped seating with knees bent; Obesity; Recent trauma from an accident or surgery (especially to legs); Decreased oxygen pressure, Oral contraceptives and hormonal replacement.

Previous DVT or varicose veins; History of malignancy; Family History; Recent surgery. These risks are not simply additive; the risk of DVT can more than double with 2 risk factors.

1. During Travel:
• Check for in-flight exercise information
• Avoid crossing legs or prolonged awkward hip or knee positions
• Stand up and walk around at least hourly
• Stand on tiptoes to exercise your calf muscles
• Drink adequate fluids-at least 1 liter per 5 hours of flight
• Avoid alcohol as it promotes fluid loss
• Wear loose fitting clothing
2. Avoid smoking
3. Discuss with your doctor any family and personal history that might pre-dispose you to develop DVT.
• Discuss whether anticoagulant therapy is suitable in your case.
4. Aspirin use is not recommended.
5. Elevate and exercise your legs when possible. Flex your ankles or press your feet against the seat in front of you. Consider compression stockings.

• www.mayoclinic.com
• www.nhlbi.nih.gov
• Medical Society's Labor Day CheckList Focuses on Air Travel.
• Labor Day Checklist - Medical Tips for Air Travel